The first thing that should be explained when it comes to the Ports Collection is what is actually meant by a “skeleton”. In a nutshell, a port skeleton is a minimal set of files that tell your FreeBSD system how to cleanly compile and install a program. Each port skeleton includes:

  • A Makefile. The Makefile contains various statements that specify how the application should be compiled and where it should be installed on your system.

  • A distinfo file. This file contains information about the files that must be downloaded to build the port, and their checksums (using md5(1) and sha256(1)), to verify that files have not been corrupted during the download.

  • A files directory. This directory contains patches to make the program compile and install on your FreeBSD system. Patches are basically small files that specify changes to particular files. They are in plain text format, and basically say “Remove line 10” or “Change line 26 to this ...”. Patches are also known as “diffs” because they are generated by the diff(1) program.

    This directory may also contain other files used to build the port.

  • A pkg-descr file. This is a more detailed, often multiple-line, description of the program.

  • A pkg-plist file. This is a list of all the files that will be installed by the port. It also tells the ports system what files to remove upon deinstallation.

Some ports have other files, such as pkg-message. The ports system uses these files to handle special situations. If you want more details on these files, and on ports in general, check out the FreeBSD Porter's Handbook.

The port includes instructions on how to build source code, but does not include the actual source code. You can get the source code from a CD-ROM or from the Internet. Source code is distributed in whatever manner the software author desires. Frequently this is a tarred and gzipped file, but it might be compressed with some other tool or even uncompressed. The program source code, whatever form it comes in, is called a “distfile”. The two methods for installing a FreeBSD port are described below.

 

Note: You must be logged in as root to install ports.

 

The Ports Collection makes an assumption that you have a working Internet connection. If you do not, you will need to put a copy of the distfile into /usr/ports/distfiles manually.

To begin, change to the directory for the port you want to install:

# cd /usr/ports/sysutils/lsof

Once inside the lsof directory, you will see the port skeleton. The next step is to compile, or “build”, the port. This is done by simply typing make at the prompt. Once you have done so, you should see something like this:

# make
>> lsof_4.57D.freebsd.tar.gz doesn't seem to exist in /usr/ports/distfiles/.
>> Attempting to fetch from ftp://lsof.itap.purdue.edu/pub/tools/unix/lsof/.
===>  Extracting for lsof-4.57
...
[extraction output snipped]
...
>> Checksum OK for lsof_4.57D.freebsd.tar.gz.
===>  Patching for lsof-4.57
===>  Applying FreeBSD patches for lsof-4.57
===>  Configuring for lsof-4.57
...
[configure output snipped]
...
===>  Building for lsof-4.57
...
[compilation output snipped]
...
#

Notice that once the compile is complete you are returned to your prompt. The next step is to install the port. In order to install it, you simply need to tack one word onto the make command, and that word is install:

# make install
===>  Installing for lsof-4.57
...
[installation output snipped]
...
===>   Generating temporary packing list
===>   Compressing manual pages for lsof-4.57
===>   Registering installation for lsof-4.57
===>  SECURITY NOTE:
      This port has installed the following binaries which execute with
      increased privileges.
#

Once you are returned to your prompt, you should be able to run the application you just installed. Since lsof is a program that runs with increased privileges, a security warning is shown. During the building and installation of ports, you should take heed of any other warnings that may appear.

It is a good idea to delete the working subdirectory, which contains all the temporary files used during compilation. Not only does it consume valuable disk space, but it would also cause problems later when upgrading to the newer version of the port.

# make clean
===>  Cleaning for lsof-4.57
#
 

Note: You can save two extra steps by just running make install clean instead of make, make install and make clean as three separate steps.


The ports system uses fetch(1) to download the files, which honors various environment variables, including FTP_PASSIVE_MODE, FTP_PROXY, and FTP_PASSWORD. You may need to set one or more of these if you are behind a firewall, or need to use an FTP/HTTP proxy. See fetch(3) for the complete list.

For users which cannot be connected all the time, the make fetch option is provided. Just run this command at the top level directory (/usr/ports) and the required files will be downloaded for you. This command will also work in the lower level categories, for example: /usr/ports/net. Note that if a port depends on libraries or other ports this will not fetch the distfiles of those ports too. Replace fetch with fetch-recursive if you want to fetch all the dependencies of a port too.

Note: You can build all the ports in a category or as a whole by running make in the top level directory, just like the aforementioned make fetch method. This is dangerous, however, as some ports cannot co-exist. In other cases, some ports can install two different files with the same filename.

In some rare cases, users may need to acquire the tarballs from a site other than the MASTER_SITES (the location where files are downloaded from). You can override the MASTER_SITES option with the following command:

# cd /usr/ports/directory
# make MASTER_SITE_OVERRIDE= 
ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/distfiles/ fetch

In this example we change the MASTER_SITES option to ftp.FreeBSD.org/pub/FreeBSD/ports/distfiles/.

Occasionally, you might also want to check dependencies of your packages (maybe to see what other packages it requires or what other packages require it). To do so is pretty easy. Just use the pkg_info command to grab this information. Let's say you wanted to know the dependencies for Perl:

# pkg_info -rR perl-5.8.9_2
Information for perl-5.8.9_2:

Depends on:
Required by:
p5-Storable-2.20
p5-DBI-1.60.7
p5-DBD-mysql-4.010
p5-Term-ANSIColor-1.12
p5-Term-ReadKey-2.30